Lawn-mower sharpener



Mar. 13', 1923. 1,448,5119.'

C. F. BROWN. LAWN MOWER SHARPE'NER.

HLED JAN. 14, 1922.

2 SHEETS-SHEET l.

INVENTOR,

WITNESSES A.

v7.2 I i 1MM@ i ATTORNEY Mar. 13, 1923.

2 sHEHs-sHET 2.

C F BROWN LAWN MOWER SHARPENER.

man 1AN.14,1922.

Patented Mar. i3, i923..

iillfailli asia satana caricia.

LAWN-Mower. SIHARPENER.

.Application filed January 14, 1922. Serial No. 529,275.

eners, of which the following is aspeciiiy cation. n

Tins mvent1on has reference to ylawn mower blade Sharpeners, and is an improvement on the lawn mower Sharpener shown and described in application No.v 453,333, y

filed by me on March 24, 1921.

In accordance with the invention the blades of the lawn mower are dismounted, and anabrasive or grinding wheel is supported in such relation to the cutter blades that the abrasive or grinding wheel ismade to travel over the blades. y

Provision is made for supporting the stationary cutter, removed from the lawn mower assembly, and to use said stationary cutter as a guide in order that both the stationary and rotary cutters may be held in related positions, whereby they will have the proper angular position of their cutting edges with respect to one another, that they should have inthe assembled lawn mower.

In accordance with the invention, clamping devices are employed for grippingthe stationary blade, and guide devices are used, for engaging the' rotary blade assembly in order to maintain the proper relation between the abrasive wheel and said rotary blades.

A full and complete understanding of the invention may be obtained from a consideration of the following detailed description taken in connection with the accompanying drawing forming a part of this specification, it being understood that while the drawing shows a practical form of the invention, the latter is not confined to strict conformity therewith, but may be changed or modified so long as such changes or modiiications mark no material departure from the salient features of the invention, as specifically pointed out in the appended claims.

In the drawing:

'Figure l isa plan View of a portion of a sharpening machine adapted vfor receiving the whole lawn mower excepting the operating handle and the roller.

Figure 2 is an end elevation of that portion of the sharpening machine mounted on the carriage.

'of the levers used to Figure 3 is a section on the line 3 3 of y Figure 2. Y

Figure et is a section on the line 4-4 of Figure 2. I

vFigure 5 is a'detail view of one of the fixed blade holders.

yco

Figure 6 is a perspective view of a'machine embodying lthe invention; and

Figure 7 is a detail in perspective of yone guide the rotary cutter bar during grinding. l y

Referring to the preferred embodiment of the invention disclosed in the drawing, there is shown a table or work support- 2 which may be considered as of any suitable shape and construction and not necessarily confined to the particular arrangement indicated. rlhe table may be considerably elongatedso as to accommodate various makes 'oflawn mowers to be sharpened..

The work support 2 constitutes means whereby an emery or similar sharpening or grinding wheel may be rotated in engagement with a cutter blade 80," which isthe stationary blade of the lawninower. Also carried by the work support 2', as best shown in Figure 6, is the rotary cutter of a lawn mower having the usual spiral blades 80a.

Adjacent to the 'work support 2 is an elongated track 17 upon which movesI a carriage 18 having an extent vof travel corresponding tothe length of the lawn mower, and appropriately shaped to reciprocate lengthwise of the machine frame. Mounted on the carriage 18 is a pedestal l37 which may be of pyramidal shape, although such particular conformation is not obligatory, but is to be preferred because the upper end of the pedestal 37 is raised to a suiiicient height for the purposes of the invention, without causing undue enlargement. At the top ofthe pedestal 37 is mounted a shaft 68a carrying a pulley 40 and a bevel pinion 74, and also carrying spacing sleeves 69a. The shaft 68a is journaled in yoke members 70 and 75, the yoke being formed in two vparts held together by a screw 76 extending through one end of the yoke member 75. The yoke member 70 has a lateral extension 71, in which is journaled a spindle 72 carrying at .one end a bevel pinion 73 meshing witl the pinion 74, Aand at the other end provided with screw-threads to receive the abrasive or grinding wheel 41 held in place thereon by a nut or any other suitable means.

The shaft 68a is driven by means of a belt 42 engaging the pulley 40,

' shaft 682i imparts y'motion to the bevel gear 74 and thence tothe bevel gear 7 3, and to the spindle 72, 4driving the abrasive-,or grind'- ing wheel 41 which may be conside-red as 'adjusted into engagement with one'oi the blades 80, In the meantime the carriage 18y is caused to travel lengthwise of the support 2;, thereby moving the abrasive wheel 41 along the support 2, so as to take an appropriate out from the blade 80a. ,j

2 is provided with al The work support longitudinalslotparallel with one long edge ofthe support 2, ,which slot is sut'- liciently elongated to 'provide l'tor a considerable ,extent foiadjustment oft y'the work v than removing the handle land usual roller,

,roller was removed.

holder, whichwill now be described.

Y The, slot. 10 is traversed by slot .13 in a foot or vbase 14 of afbracket 15 carrying at one end a socket member 16, designed to receive a work holder, in turn to receive and se- ...cure the bladeassembly ot the lawn mover,

all-as vshown in the aforesaid vapplication No. 453,333.

f .Vlfhen itis desired 'to grind they blades without dismantling the lawn mower further supporting arms19 are l.mounted in brackets 15,and in turn are made fast' to that part .of the lawn mower frame from which the The grinding wheel 41 is suihciently ele.-

vated, with respect to the work support 2,2toy bring the grinding wheel in proper vove,rhanging position with respect to the bar blades in screw 71h, also carrying a jam nut 69?, wherev by the headed screwl 711? may be `locked in position,

Vand constitutes an adjustable stop Vmember `on one end of a lever 72a, mounted on the iframe 71.-

The angle lever 71 at the end remote from the screw V71b is provided with another set screw 71.,Ato whichv is .applied a thumb nut 71?, they spring 711 being compressed by the thumb nut 71e, whereby the tension voi" the spring 71dfmay be adjusted at will',` so as'tocause the screw 71b to clamp the cutter blade 8O against the bent end 72d ot the pin/7.2.

Also mounted on lthe frame 71 is a rock arm 73h having at the other side anangle extension 7 3a, the arm 731 being engagea-ble whereby the along, a bolt 11 to caused to which is applied a clamp nut 12 said bolt 11l vtraversing an elongated for clamping or` holding the sta-- ,tionary cutter blade 8O against the bent end 72'? of a pin 7 2c, carried by avrock shaft 7 2*y under the arm 72n and operable by reason A of the arm 73, at will.

Fast to the frame 71 is back stop for the cutterbbla'de 80a, holding said cutter blade at the proper angle to the grinding wheel 41, to give to the cutter blade 80a the'properbevel. This pin 41 bears against the blade and maintains it underneath the grinding wheel when thecariiage is in motion. The cutter blade tween the angle extension 72d 4andthe set-screw 71", serves grinding wheel. in engagement with the cutter blade 80a, and as the carriage 18 moves the assembly ot cutter blades 8O? is be rotated by the Contact of" the with the side of the blade 80a.

so which is' heid t@- ot the pin 72Cr finger 41a To support the stationary cutter ybar :'80,

while being` sharpened, `such cutterfbar is removedptrom the lawn mower and for it the threaded angle ySpin 41a (Fig. 2) serving" as an adjustable to hold the there is provided a cutter bar holdei` shown.

separately' yin Figure 5. This holder has a pin lextension' to enter 'the socket 116. therev c being .two such holders vto'fcarry the op A bar.

screws 89, y j

lt is to be noted that the grinding ofthe blades and the presentation of said blades oosite lends vof the ystationary cutter fach of these holders hasI a 'head S7 with oppositely disposed recesses 88', and setto the'gi'iiiiding element is automatic as'in .Q

the laforesaid applicationor'lietters Patent,

`and while an electric motor is preferred as the prime mover, because particularly adaptedA 'torthe purpose,. other prime movers vmay Y be employed.

'- f W hat is claimed is: l

1.k In a lawn mowersharpener,means'for T si'ip'portinggboth the rotary andthe stationary straight cutters when assembled, means for sharpening the blades'otl the cutters,

means `to, cause vthe sharpening means to travel longitudinally off the cutter blades,y

and means engaging with thejstraight cutvrter of the lawn mower and adaptedto move along said cutter as the sharpening means travels over the rotary spiral cutters, whereby the sharpening means is held againstthe work. Y

f t2. ln alawn mower sharpeiienmeans fior supporting both the rotary'y and the station'- i ary straight cutters vwhen assembled, means for sharpening thefblades of 'the cutters, means vto cause thefsharpeningmeans to travel longitudinally ofthe cutter blades',

means engaging with the straight cutter Aof the lawn mowerand adaptedfto move along said cutter as the sharpening means travels over the rotary'spiral cutters, whereby thev sharpening means is'beld against the work,

and means enga-ging with the spiral cutter i .l

blade which is being sharpened and holding said blade against-the sharpening means dur"- ing travel thereof by causing the rotary cutter to rotate on its support.

3. In a lawn mower Sharpener, means for supporting the rotary and stationary out. ters when assembled, means forv engaging the stationary cutter bar, a rock lever having means `for engaging the stationary cutter bar, a setscrew for determining the location of the grinding means with relation to' the rotatable cutter bars, and means cooperating with the stationary cutter-bail engaging means for holding the grinding wheel in said operative relation to the cutter bars.

e. In a lawn mower Sharpener, means for supporting the rotary and stationary cutters when assembled, means for inding the 'edges of the cutters, a rock ever having means at one end for engaging the stationary cutter bar of the lawn mower, elastic means at the other end of the rock lever for adjusting the degree of engagement of the rock lever with the stationary cutter bar, another rock lever having means `for engaging the stationary cutter bar to move the latter into engagement with the first named rock lever to clamp the cutter bar, and a third rook lever in position to engage the second named rock lever to clamp the several rook levers in engagement with the cutter bar.

5. In a lawn mower Sharpener, the combination with a xed support for the rotary cutters, a frame, a grinding wheel mounted thereon, and a pin carried by the frame and having its lower end bent outwardly beneath said wheel to engage a rotary cutter of the lawn mower for maintaining the cutter bar in position against the grinding wheel.

6. In a lawn mower Sharpener, the combination with a frame carrying al grinding wheel, and means to support the knife assembly of the mower, of a rock leve-r carried by the grinder :trame and having means to engage the upper side of the stationary cutter bar, and a second rock lever carried by the grinder frame and having means to engage the under side of said cutter bar, whereby the grinder frame is held in the lesired position.

7. In a lawn mower Sharpener, the combination with means to support the knife assembly of the mower, of a frame, a grinding wheel mounted thereon, rockable means to engage with the upper side ot' the stationary cutter baroi: the lawn mower, another rockable means to engage'with the underside ot the said cutter bar to clampfthe cutter bar in cooperation with the iirst-named rockable means, and means for operating the second named rockable means to move the same into and out of engagement with said cutter bar.

8. In a lawn mower Sharpener, a support for the mower, a reciprocatory carriage, grinding means supported on the carriage, means on the grinder support and engaging with the blades for rotating the rotary blade assembly upon fthe progressive movement of the grinding means lengthwise of the blades, andhmeans tor slidablyconnecting the grinding means to the stationaryf'cutter blade of the mower to maintain the grinding means and blades in proper rela* tiony for sharpening.

9. Ina lawn mower Sharpener, a support for the lawn mower,"a grinder, a grinder sup-port, means causing said grinder support to trave-l, means mounted on the grinder support for clamping the stationary blade of the lawn mower to maintain the grinder and rotary blade assembly in sharpening relation, and operator controlled means for releasing said clamping means.

l0. In a lawn mower Sharpener, a reciprocable carriage, a pedestal carried thereby, p means for supporting the rotatable blade assembly of the lawn mower, and means for causing the rotation thereofupon reciprocation of the carriage, an arm pivotally mounted on the pedestal and overhanging the rotatable blade assembly, a grinder on the overhanging arm located to engage one of the blades, a guide carried by the overhanging arm adjacentI to the grinder, and means for supporting the arm at the grinding end by the stationary cutter blade of the lawn mower.

1l. In a lawn mower Sharpener, a reciprocable carriage, a rockable yoke arm mounted at one end on the carriage, aspindle carried by and traversing the yoke arm, a gear drive for one end of the spindle, a grinding wheel on the other end of the spindle, clampingimeans on the yoke arm adapted tol engage the stationary cutter blade of the lawn mower, and means on the yoke arm for engaging a chosen one of the assembly of rotatable cutter blades of the lawn mower to cause them to be rotated by the re# ciprocation of the carriage.

12. In a lawn mower Sharpener, clamping means for utilizing the stationary blade of the lawn mower as a guide, a rockable yokev provided with an adjustable clamp member for the cutter blade, and another clamp member coacting with the first named clamp member for locking both clamp members together upon the stationary blade.

13. In a lawn mower Sharpener, the combination with a reciprocable carriage, a shaft thereon having meansfor driving it, a grinding wheel carried by the carriage and geared to the shaft in position to engage the cutting blades of a rotatable blade assembly mounted on the carriage, means for mounting the stationary cutter bar of the lawn mower on the carriage, and clamping means for engaging the stationary cutter bar, to hold the grinding wheel in operative relation to the assembly of rotatable blades.

14. In a lawn mower Sharpener, the cornbination with a reciprocable carriage, a

yshaft.thereon havngineas forfdlfxnzingytr, a 'grinding Wheel ear-piedby the carnage and geared tol the shaft in postonto engage Vthe cuqtrngblades of ya4 'rQ'tat'ablebla-de assembly mountedon. they carriage, means for mounting the stationary cuttery ybei' of the lawn mower en the carriage, c lampllgneansd 'orl engaging. the statonaryhutte bar -to hold vthef.ginding Wheel n operative vrelation to T0 the lassembly of rotateble` bledeg animee/ns 1 nature. `v

mounted .on the carriagefaid eugaffgngwith the blade Which-is beiIigY- Qpegated yupolnloygas, my Own, I

.Saidblfavcle,v Said meanslcontaing with the. f 

